1. Field of the Invention
The present invention relates to an optical fiber array plate, and more specifically, to an optical fiber array plate for an optical reading system.
2. Description of the Background
An optical fiber array plate for an optical reading system comprises an optical fiber array sandwiched by outer glass layers. This optical fiber array is composed of parallel array of a great number of optical fibers. In the conventional optical fibers to be used as an image guide of an optical reading system, a light absorber is provided in surrounding or interstitial relation with a cladding of optical fibers, to prevent leakage of light and thereby to improve the image-transmission efficiency.
In case of the fiber plate composed of optical fibers having a light absorber used in contact with the paper surface of the original for reading, it is necessary to cut off the portion of the fiber array plate which hinders the incident ray from a light source in order to permit the incident ray to directly irradiate the paper surface of the original. Accordingly, the number of facets to be cut and polished increases, and consequently the production costs will increase.
The present invention is an improvement of such a conventional optical fiber array plate, wherein the light absorber is removed from the optical fibers constituting the optical fiber array, and the incident ray is permitted to pass through this optical fiber array at some angles and irradiate the original, and the reflected ray is led through the optical fiber array to a photoelectric converter.
Namely, the present invention provides an optical fiber array plate for an optical reading system, which comprises an optical fiber array sandwiched by outer glass layers, characterized in that said optical fiber array is composed of parallel array of a great number of optical fibers having no light absorber, and the arrangement is such that an incident ray is led to pass through the outer glass layers and the optical fiber array and irradiate an original placed at a reading end surface of the optical fiber array and the reflected ray from the original is led through the optical fibers to a photoelectric converter.